pGH 20kDa Human

Growth Hormone Placental 20kDa (Human Recombinant), often abbreviated as GH-V, is a variant of human growth hormone (hGH) produced in the placenta. Unlike the pituitary-derived human growth hormone (hGH-N), which is a 22-kilodalton (kDa) protein, GH-V is a 20-kDa protein. This variant is produced through recombinant DNA technology, which allows for the synthesis of proteins identical to those naturally occurring in the human body.

GH-V is a single, non-glycosylated polypeptide chain containing 177 amino acids and has a molecular mass of approximately 20,498 Daltons . It is expressed in the syncytiotrophoblast and extravillous cytotrophoblast layers of the human placenta. The levels of GH-V increase throughout pregnancy and eventually replace hGH-N in the maternal circulation .

GH-V plays a crucial role in regulating in utero growth and development. It has similar somatogenic effects to hGH-N but with reduced lactogenic activity . This means that while GH-V promotes growth, it does not stimulate the production of milk as effectively as hGH-N. Additionally, GH-V has been shown to have a beneficial reduction in diabetogenic activity, making it a potentially safer alternative for therapeutic use .

The recombinant form of GH-V is produced using Escherichia coli (E. coli) as the host organism. The gene encoding GH-V is inserted into the bacterial DNA, allowing the bacteria to produce the protein. The protein is then purified through various biochemical techniques to ensure its purity and functionality .

Studies have shown that GH-V can stimulate insulin-like growth factor-1 (IGF-1) and subsequent longitudinal body growth in GH-deficient models, similar to hGH-N . However, unlike hGH-N, GH-V does not inhibit insulin action or promote the growth of prolactin receptor-positive cancers . This makes GH-V a promising candidate for growth hormone therapies, especially for individuals at risk for metabolic syndrome or certain types of cancer.